Answer:
A decrease in crop diversity.
Explanation:
Developing genetically modified crops with the purpose of having stronger immunity against weed killer is of major environmental concern. This resistance will help the GM plants survive and use most of the nutrients and resources. Nevertheless, other crop plants, which are growing in the same area, would not be able to survive and this could lead to an overall decrease in crop diversity. Such a decrease in diversity is definitely not good for the biogeochemical cycles.
